Wheelchair and scooter accessory designs that provide weather protection mainly comprise of manually mounted and operated mechanisms such as the U.S. Pat. No. 6,254,116 issued to Szumlic and Gallagher on Jul. 3, 2001. This invention comprises of a telescoping shaft with an angular disposition mechanism that allows an umbrella to be manually mounted and handled by a wheelchair-bound person. This design is adequate for a handicap person with substantial upper body mobility and function. For the handicap person who is incapable of manually inserting, opening, and maneuvering an umbrella in a shaft, a more automatic mechanism is required.
Another invention that allows an umbrella to be manually inserted into a fitting and mounted on a wheelchair is U.S. Pat. No. 6,711,769, issued to Jane-Prats on Mar. 30, 2004. The invention provides the means to manually control an umbrella with a mechanism that can rotate and swivel. The invention has a mechanism that clamps onto a pillow and provides a fitting for an umbrella. The invention was initially intended for sunbathers but is currently being marketed as a wheelchair accessory. Once again, this design is adequate for a handicap or elderly person who has substantial upper body mobility and function. A person with further limitation requires automation or assistance from a secondary party.
Sun protection accessories for wheelchairs and scooters also consist of manually mounted canopies, such as the U.S. Pat. No. 5,168,889 issued to Diestel on Dec. 8, 1992. This invention is a manually mounted and removable canopy that provides weather and sun protection for wheelchairs. It can also be manually dismantled and stored away in a cylindrical container. The task of manually mounting, assembling, disassembling and storing the canopy is labor intense and difficult for the average handicap person. Essentially, the assembly and disassembly requires the aid of an able-bodied person. Therefore, this invention does not promote independence amongst persons with limited upper body mobility.
Protective canopies are applied to different mechanisms in a variety of industries. They also range in complexity; for example U.S. Pat. No. 5,511,259 issued to Tarrara on Apr. 30, 1996 is a simple manually driven collapsible canopy for a stretcher. This invention consists of 4 U-shaped members which are pivotally joined at the same junction point on a stretcher. The purpose of this invention is to provide privacy to hospital patients that are placed on the stretcher. A comparable complex protective canopy is U.S. Pat. No. 6,336,673 issued to Rothe, Rieste, Weissmueller, and Bramsche on Jan. 8, 2002. This invention is a convertible roof for an automobile; it consists of two separate roof sections which are relocated from a stored position within the trunk space to the roof position.
Another patent is U.S. Pat. No. 5,921,258, the “Adjustable Removable Weather Shield for a Wheelchair” issued to Wade Francois on Nov. 24, 1997. This invention is a collapsible weather shield for wheelchairs; it provides a manually operated or motor activated protective canopy. The structural members relocate from behind the backrest to the operating position above the wheelchair. The flaw with this design is that it is highly conceptual and impractical. For example, the motor is directly mounted to the shaft that drives the canopy structure. This assembly is prone to mechanical failure. If the canopy is lifted, pushed, or rotated to counteract the motor's rotational force, immediate mechanical damage will occur to the motor. This is likely to happen if wind loads, human tempering or mechanical impact is applied. In addition, the canopy will be highly unstable, since the motor is the only acting braking force when the canopy is in the open or operating position and the collapsed upright position. Also, the U-shaped structural members open and retract with a spring-loaded pulley mechanism driven by the same motor. This assembly results in a highly fragile canopy. The pulley mechanism will have slack in the open position, making it prone to mechanical damage. Consequently, the spring provides an inconsistent force required to maintain the canopy structurally sound in the open position.
Other impracticalities exist in various aspects of the design. For example; the required rotational speed for the canopy to open is roughly one (1) RPM, which is slower than standard motors on the market. Therefore, a non-standard motor is required, since a step down mechanism is not shown in the design. Also, the location of the motor increases the overall width, which reduces maneuverability and makes the invention prone to mechanical damage by impact.
In general, the history of weather protection accessories for mobility devices such as power wheelchairs and scooters does not promote independence amongst individuals with limited abilities. The majority of mechanisms require from an able-bodied secondary party to exert a significant amount of work to operate them. The only invention that provides some form of automated weather protection is the “Adjustable Removable Weather Shield”, which presents numerous flaws and is highly conceptual and impractical.